The bale-forming belts in known variable chamber balers are supported by a combination of fixed and movable belt support rolls, with some of the movable belt support rolls being carried by tensioning arms mounted for vertical pivotal movement, so as to control loops of excess lengths of bale-forming belts, at a start of a bale, with the tensioning arms being biased so as to yieldably resist movement in a direction permitting lengths of belting to be pulled out from the loops as the bale expands in size. The density of the formed bale depends upon the resistance to the belt expansion during formation of the bale. Once formation of the bale is completed, a discharge of the bale from the baling chamber is accomplished by opening a bale discharge gate which elevates a section of the bale-forming belts away from the lower rear portion of the bale so as to release it for discharge. U.S. Pat. No. 4,433,619 discloses a baler of this type. The baling process sometimes results in the formed bale becoming wedged between fixed sidewalls of the baling chamber. To overcome this problem, designers of some of these known balers have supported the bale-forming belts such that the belts tighten during the ejection process and help push the bale from the baling chamber. An example of a baler of this type is disclosed in U.S. Pat. No. 6,640,699.
Various embodiments of particularly useful tensioning arm arrangements are disclosed in U.S. patent application Ser. Nos. 11/109,079 and 11/109,585, which were each filed on Apr. 19, 2005. The tensioning arm arrangements of all of these embodiments are associated with a baler having a so-called light weight discharge gate comprising a triangular gate member having opposite triangular ends including respective first corners respectively pivotally mounted to opposite sidewalls of the baling chamber for pivoting about an axis located so as to be approximately at the central axis of a full sized bale formed in the baling chamber, with the triangular discharge gate member being located in a lowered position with rolls at front and rear corners guiding a lower run of the bale-forming belts during baling operation, and being swung to a raised discharge position permitting a formed bale to pass beneath the bale-forming belts and exit the baling chamber.
A drawback associated with the tensioning arm arrangement disclosed in U.S. Pat. No. 6,640,699 and with the tensioning arm arrangements disclosed in the above-identified patent applications is that bale ejection is not positive enough to consistently effect the discharge of a wedged bale. A further drawback associated with the tensioning arm arrangements disclosed in the above-identified patent applications is that the tensioning arm arrangements are not readily adaptable for being used with a baler that, instead of having a light weight discharge gate, has a baling chamber including a discharge gate comprising rear sidewall portions which carry baling belt support rolls and are pivotally mounted to upper rear corner regions of fixed front sections of the sidewalls for moving between a lowered baling position and a raised bale discharge position.
The problem to be solved with the present invention is that of providing a tensioning arm arrangement which provides positive bale ejection while being easily adaptable for use with balers having either a light weight discharge gate, or the more conventional discharge gate including pivotable baling chamber sidewall portions.